IMPROVED DESIGN OF THE SCREW PRESS COUPLING

Abstract

Purpose. The aim of the work is to increase the energy efficiency and operational reliability of heavy screw presses by creating a new drive design that ensures stabilization of the load on the power grid and eliminates thermal overloads of the electric motor.

Research methods. The study employs a critical analysis of modern technical solutions from leading manufacturers (Weingarten, Hasenclever), specifically the RZS series with direct drive. The research utilizes the general theory of electric drives to analyze energy efficiency in transient modes. Kinematic analysis and analytical calculations of the moment of inertia were performed to substantiate the method of separating the driving mass (kinetic energy accumulator) into multiple components to reduce inertial loads.

Results. The operational limitations of direct-drive presses, such as high peak currents and thermal overloads, were identified. A new screw press design was proposed featuring a kinetic energy accumulator consisting of a central driving flywheel and lateral driving masses mounted on the motor shafts. This accumulator is connected via a clutch to the working driven flywheel of the press. Separating the driving accumulator into segments allows for a 25-fold reduction in the mass of the driving elements while maintaining the same kinetic energy. To optimize the reverse stroke, the working flywheel itself is also divided into two parts: an inner flywheel (rigidly mounted on the spindle) and an outer flywheel (which is disengaged during the upward stroke of the slide). Recommendations for an autonomous reverse stroke system were provided.

Scientific novelty. A method for separating rotating masses into a continuously operating kinetic energy accumulator (driving flywheel system) and a cyclically connected working element is proposed. Unlike traditional rigid-connection drives, the new kinematic scheme utilizes an intermediate driving mass and a friction clutch, allowing the motor to operate continuously without frequent high-current starts.

Practical value. The design is applicable for presses with a nominal force from 2 MN and energy up to 5 MJ, suitable for precision forging of turbine blades and gears without stamping inclinations. The use of standard induction motors and the reduction of the drive's metal consumption decrease manufacturing and modernization costs while improving power grid stability.